Displaying items by tag: biocement
Princeton University team develops bio-based cement with increased toughness and ductility
26 June 2024US: A team at the University of Princeton has developed a new alternative cement using oyster shells. The team says that the oyster shells provide calcium carbonate in the form of aragonite, along with biopolymers. Together, these raise the resulting cement’s crack resistance by 19% and its ductility by 17% compared with ordinary Portland cement (OPC).
Team leader Reza Moini said “Our bio-inspired approach is not to simply mimic nature’s microstructure, but to learn from the underlying principles and use that to inform the engineering of human-made materials. One of the key mechanisms that makes a nacreous shell tough is the sliding of the tablet at the nanometer level. Here, we focus on the mechanism of tablet sliding by engineering the built-in tabulated structure of cement paste in balance with the properties of the polymer and the interface between them. In other words, we intentionally engineer defects in the brittle materials as a way to make them stronger by design.“
10 sustainable cement and concrete technology developers launch the Decarbonized Cement and Concrete Alliance
18 January 2024North America: A new coalition for the scaling and deployment of low-carbon building materials, the creation of new clean cement and concrete jobs and the promotion of environmental justice launched earlier in January 2024. Called the Decarbonized Cement and Concrete Alliance (DC2), it comprises alternative cement developers Biomason, Brimstone, Chement, Fortera and Terra CO2, sequestration company Blue Planet Systems, circular concrete producer CarbonBuilt, biogenic limestone producer Minus Materials, hydrothermal processing technology developer Queens Carbon and electrified cement production technology developer Sublime Systems. DC2’s areas of engagement in policy will include tax credits, standards, ecolabeling and subsidisation, in line with the US Department of Energy’s Pathways to Commercial Liftoff: Low-Carbon Cement strategy.
CarbonBuilt’s government and community affairs manager Sal Brzozowski said “DC2’s platform of robust policy, standards and incentives to scale innovative solutions will not only accelerate deep decarbonisation, but also transform the concrete industry from one of the world’s largest CO2 emitters to one of the world’s largest carbon sinks.”
US: Prometheus Materials' microalgae-based biocement has demonstrated 12 times greater sound absorption than ordinary Portland cement (OPC). Prometheus Materials produces its biocement at ambient temperature, with no process CO2 emissions.
Egypt: Researchers at the University of Cairo have used nanomaterials from agricultural wastes to produce biocement with 'increased strength and durability' compared to ordinary Portland cement (OPC). The study employed microbially induced calcite precipitation (MICP) with the addition of carbon nitride nanosheets and ash from waste maize cobs. Besides its improved physical performance, the researchers also found that their biocement offers improved endurance against water permeability.
Prometheus Materials secures concrete masonry unit certificates for microalgae-based biocement
22 February 2023US: Prometheus Materials’ microalgae-based biocement has secured certification for use in concrete masonry unit (CMU) mixes. The cement now holds an ASTM C129 certificate for use in non-loadbearing CMUs and an ASTM C90 certificate for use in loadbearing CMUs. Prometheus Materials’ biocement produces concrete with comparable or superior mechanical, physical and thermal properties to ordinary Portland cement (OPC)-based concrete. It offers little-to-no CO2 emissions and 95% of water used in production is recycled.
Prometheus Materials CEO Loren Burnett said “We are thrilled to have achieved these two foundational certifications as we proceed in full force with our goal of decarbonising construction. Prometheus Materials’ product is poised to change the future of construction, converting one of the most carbon-polluting industries to a low-carbon – and one day net-zero carbon – reality.”
US: Prometheus Materials has been awarded ASTM C129 certification for non-loadbearing concrete masonry units (CMU) and ASTM C90 for loadbearing CMUs for its bio-cement product. The company is commercialising a process to produce cement and concrete using microalgae.
Loren Burnett, the chief executive officer of Prometheus Materials, said “We are thrilled to have achieved these two foundational certifications as we proceed in full-force with our goal of decarbonising construction.” He added, “Prometheus Materials’ product is poised to change the future of construction, converting one of the most carbon-polluting industries to a low-carbon – and one day net-zero carbon – reality.”
Signapore: Researchers at the Nanyang Technological University in Singapore (NTU Singapore) have successfully used bacteria to combine two abundant waste streams into clinker-free biocement. NDTV news has reported that the scientists developed the material from by combining calcium ions with urea in a mixture of industrial carbide sludge and urine. The process takes place at room temperature, reducing CO2 emissions while also offering waste management benefits.
The NTU Singapore team is presently testing the biocement on artificial beaches. It will subsequently investigate other possible large-scale applications around Singapore.